Answer:
<em>D. The acceleration after it leaves the hand is 10 m/s/s downwards
</em>
Explanation:
<u>Vertical Throw
</u>
When an object is thrown upwards, it describes a special type of motion ruled only by gravity.
When the ball is launched, it has its maximum speed upwards. The acceleration of gravity is always the same because it's a constant value near our planet's surface. The object starts to lose speed since the acceleration of gravity is pointed downwards and makes the object stop in the mid-air at its maximum height, where the speed is zero. Then, the object starts to fall and regain speed, this time downwards until it reaches back the launching point at the very same speed it was launched, but in the opposite direction.
The time it takes to reach its maximum height is the same it takes to return to the catching point, 2 seconds later.
With all these concepts in mind, we state that:
<em>D. The acceleration after it leaves the hand is 10 m/s/s downwards </em>
The other options are not correct because:
A. The acceleration is never upwards
B. The acceleration is never 0
C. Both times are equal
Answer:
<em>The mass of the apple is 0.172 kg (172 g)</em>
Explanation:
<u>The Law Of Conservation Of Linear Momentum
</u>
The total momentum of a system of bodies is conserved unless an external force is applied to it. The formula for the momentum of a body with mass m and speed v is
P=mv.
If we have a system of two bodies, then the total momentum is the sum of both momentums:
If a collision occurs and the velocities change to v', the final momentum is:
Since the total momentum is conserved, then:
P = P'
Or, equivalently:
If both masses stick together after the collision at a common speed v', then:
We are given the mass of an arrow m1=43 g = 0.043 kg traveling at v1=84 m/s to the right (positive direction). It strikes an apple of unknown mass m2 originally at rest (v2=0). The common speed after they collide is v'=16.8 m/s.
We need to solve the last equation for m2:
Factoring m2 and m1:
Solving:
Substituting:
The mass of the apple is 0.172 kg (172 g)
Answer:
Explanation:
Givens
vi = 0
a = 9.81
d = 4.50 m
vf = ?
Formula
vf^2 = vi^2 + 2 * a * d
Solution
Substitute the knowns into the formula
vf^2 =0 + 2 * 9.81 * 4.50
vf^2 = 88.29 Take the square root of both sides.
sqrt(vf^2) = sqrt(88.29)
vf = 9.40 m/s
Rutherford tested Thomson'shypothesis by devising his "gold foil" experiment. Rutherford was forced to discard the Plum Pudding modeland reasoned that the only way the alpha particles could be deflected backwards was if most of the mass in an atom was concentrated in a nucleus.
